The present invention refers to a process fortreating linenized cork sheets, improving its mechanical and tactile features.
As it is well known, cork is obtained from the bark of some trees, in particular the cork oak, without uprooting them. It has some interesting properties such as impermeability, imputrescibility, remarkable elasticity and it is also insulating.
For this reason, as well as for its being easy to manufacture, cork can be used in several fields. One of the most common is its reduction in thin sheets that adhere to an adhesive cloth, obtaining linenized cork sheets that can be employed, for example, as wallpaper, upholstery or for suitcases etc.
This kind of sheets, which are some tenths of millimeter thick, when folded gets creased, losing most of its pleasant appearance. Furthermore, cork is somehow paper-like rough to the feel.
These drawbacks, making cork features more similar to those of paper than to those of fabric, prevent its use in the textile or in the leather fields to replace animal or imitation leather, for example in the manufacturing of shoes, bags or wallets, where a crease-resisting and velvetlike to the feel material is required.
Some methods to soften cork, reducing its surface roughness by employing glycerol superficially applied thereto, are known. However, such systems cannot manufacture linenized cork sheets behaving substantially like fabric or leather.
Cork-based coatings are disclosed in JP-A-84-272752, U.S. Pat. No. 1,608,243 and DE 42 44 250-A1.
The technical problem at the basis of the present invention is to provide a treating process to avoid the drawbacks cited with reference to the state of the art.
Such problem is solved by a process for treating linenized cork sheets employing a surfactant emollient agent, including the steps of:
diluting said emollient agent with water obtaining a diluted emollient mixture;
preparing a absorbing sheet apt to be soaked with liquid, and inducing the absorption, of said emollient mixture in said layer by immersing said layer in a bath realised with said emollient mixture; and
putting said soaked absorbing sheet (1) in a surface-to-surface contact with a linenized cork sheet (2) at its linenized surface (3), keeping this contact to allow an emollient agent transfer from the absorbing sheet (1) to the linenized cork sheet (2).
The main advantage of the process according to the present invention lies in the obtainment of crease-resisting linenized cork sheets that can be folded without showing marks or permanent creases. Furthermore, these sheets in their non linenized surface, are velvetlike and pleasant to the feel.
For such features, the cork sheets thereby obtained can be employed in dressmaking and leather, as well as in upholstery and wall coating, keeping also the qualities of cork in general intact.